There's always been a long tail in the demand curve, and it always will.
What we need are useful recommendations that guide us from the head to the hidden treasures located along the tail area.

Also, I find very disappointing that none (Wharton, Anderson, etc.) uses the Long Tail model proposed by Kalevi Kilkki ( http://firstmonday.org/htbin/cgiwrap/bin/ojs/index.php/fm/article/view/1832/1716 ). This model has a better formal definition of the Head, Mid and Tail parts of the curve (not based neither on absolute nor on %), based on how to split the (log) x-axis.

[shameless plug] I did a PhD named "Music Recommendation and Discovery in the Long Tail" http://www.iua.upf.es/~ocelma/PhD/index.html
So, I also did some boring analyses about the Long Tail in the music (recommendation) domain.

There is still one more music recommender system left, named FOAFING THE MUSIC. And, if you have a last.fm account, it can import all the info from there! I bet you'll discover a bunch of new artists (even coming from magnatune.com, garageband.com, cdbaby.com and lots of more cool music sites!). Enjoy!